November 11, 1921 – The first Unknown Soldier is reburied at Arlington National Cemetery. The tomb has the words inscribed, “Here rests in honored glory An American Soldier Known but to God.”

May 13, 1938 – Armistice Day becomes a federal holiday.

June 1, 1954 – President Eisenhower signs a bill changing Armistice Day to Veterans Day in order to include all U.S. veterans.

May 30, 1958 – Unknown Soldiers from World War II and the Korean War are reburied next to the Unknown Soldier from World War I.

1968 – Congress changes the date of Veterans Day to the fourth Monday in October in order to give federal employees a three-day weekend. The change begins in 1971.

September 25, 1975 – President Gerald Ford changes the date of Veterans Day back to November 11. The change begins in 1978.

May 28, 1984 – An unknown soldier from the Vietnam War is reburied in Arlington National Cemetery. In 1998, he is identified through DNA tests as Michael Blassie, a 24-year-old pilot shot down in 1972 on the border of Cambodia.